Commissioning, Characterisation and Temperature Stabilisation of a 22000 Channel SiPM-on-Tile Hadron Calorimeter System

With the successful construction and operation of a highly granular hadron calorimeter system, featuring approx. 22000 individually read out SiPM-on-tile channels, the CALICE collaboration has set the next milestone in proving the scalability of the concept for a future high energy linear collider experiment. For this large sample of photosensors a new approach of quality control was required to sufficiently characterise and monitor device parameters for both, test bench and in-situ beam test data. In the presence of temperature fluctuations during operation, it was possible to stabilise the SiPM responses with a fully automated adjustment of the bias voltage based on frequent temperature measurements, thanks to the excellent parameter uniformity of the devices. This contribution presents the results of SiPM parameter studies during the construction and commissioning phase and reports about the system performance and the experience of automated temperature compensation at system level during operation.Comment: 4 pages, 8 figures, proceedings for 9th conference on new developments in photodetection NDIP20, Troyes (France), 04-08. July 2022, corresponding to poster P01-04. Preprint submitted to Nucl.Instrum.Meth.

Phosphorylierungsspektrum BMP- abhängiger intrazellulärer Signalwege nach Aktivierung

Bone morphogenetic proteins (BMPs) als Mitglieder der TGF-β Superfamilie sind maßgeblich an der Regulation einer Vielzahl extra- und intrazellulärer Prozesse involviert. Sie üben sowohl aktivierende als auch inhibierende Wirkungen auf die Zelle aus und spielen eine entscheidende Rolle in der Tumorbiologie des Mammakarzinoms. Die BMP-bedingte Modulation und Modifikation der Signalwege erfolgt sowohl im Extrazellulärraum, auf der Liganden-Rezeptorebene und intrazellulär durch die Signalkaskaden. Die vorliegende Arbeit beschäftigte sich mit dem zeit- und konzentrationsabhängigen Einfluss ausgewählter BMPs auf die Aktivitätssteigerung endogener Signalmoleküle unterschiedlicher Transduktions- und Transkriptionswege anhand der Mammakarzinom-Zelllinie MCF-7. Dazu dienten verschiedene molekularbiologische Verfahren. Anhand von drei differenten Signalwegen (Smad, AKT, p38 und ERK1/2 MAP Kinase) wurden die Effekte von BMP-2, BMP-3, BMP-6 und BMP-7 experimentell untersucht. Mithilfe phosphorylierter und nicht phosphorylierter Antikörper konnte die Aktivität ausgewählter Signalproteine bestimmt werden. Die erhobenen Daten unterstützen die Hypothese, dass BMP-2, BMP-6 und BMP-7 die Tumorprogression begünstigen. BMP-3 hingegen wird aufgrund der inhibierenden Effekte seiner Sonderrolle in der TGF-β Superfamilie gerecht. Es konnte bestätigt werden, dass die biologische Aktivität der Zelle von Schwellenwerten abhängt und zeitabhängig die Bindungsaffinität des Liganden am Rezeptor variiert bzw. ein ausgeprägter Konzentrationsgradient in Zusammenhang mit der Expressionsdauer verantwortlich ist. Insgesamt können im Rahmen der vorliegenden Arbeit Aspekte der Komplexität sowohl inhibierender als auch aktivierender Effekte von BMPs genauer verstanden werden. Einige bekannte Interaktionen konnten genauer spezifiziert werden, bisher nicht beschriebene Sachverhalte wie die Aktivierung von AKT-Kinase durch Inkubation der Zellen mit BMP-6 konnten neu herausgearbeitet werden

Water-Blown Polyurethane Foams Showing a Reversible Shape-Memory Effect

Water-blown polyurethane (PU) foams are of enormous technological interest as they are widely applied in various fields, i.e., consumer goods, medicine, automotive or aerospace industries. The discovery of the one-way shape-memory effect in PU foams provided a fresh impetus for extensive investigations on porous polymeric actuators over the past decades. High expansion ratios during the shape-recovery are of special interest when big volume changes are required, for example to fill an aneurysm during micro-invasive surgery or save space during transportation. However, the need to program the foams before each operation cycle could be a drawback impeding the entry of shape- memory polymeric (SMP) foams to our daily life. Here, we showed that a reversible shape-memory effect (rSME) is achievable for polyurethane water- blown semicrystalline foams. We selected commercially available crystallizable poly(ε-caprolactone)-diols of different molecular weight for foams synthesis, followed by investigations of morphology, thermal, thermomechanical and shape- memory properties of obtained compositions. Densities of synthesized foams varied from 110 to 180 kg∙m−3, while peak melting temperatures were composition-dependent and changed from 36 to 47 °C, while the melting temperature interval was around 15 K. All semicrystalline foams exhibited excellent one-way SME with shape-fixity ratios slightly above 100% and shape- recovery ratios from the second cycle of 99%. The composition with broad distribution of molecular weights of poly(ε-caprolactone)-diols exhibited an rSME of about 12% upon cyclic heating and cooling from Tlow = 10 °C and Thigh = 47 °C. We anticipate that our experimental study opens a field of systematic investigation of rSMEs in porous polymeric materials on macro and micro scale and extend the application of water-blown polyurethane foams to, e.g., protective covers with zero thermal expansion or even cushions adjustable to a certain body shape. View Full-Tex

Model based analysis of the effect of 2-ethylphenol addition to n-decane in fluid catalytic cracking over a series of zeolites

The catalytic cracking of n-decane (C10) purely, representing the conventional gasoil feed, and in admixture with 2-ethylphenol (EP), as a model component for HDO bio-oil, is investigated in a fixed-bed reactor over three faujasites. It was observed that EP induces faster deactivation with time-on-stream (TOS), which was more pronounced when materials with low mesoporous surface area were employed. The gasoline selectivity was also shown to increase more steeply with TOS for an EP containing feed. A 5-lump FCC kinetic model, including selective deactivation functions, was developed and incorporated into a transient reactor model to assess the obtained data and account for the observed effects. With the aid of the model, the above trends were rationalized by an increase in the value of the frequency factors, related to the feed conversion into coke and gasoline. The FCC kinetic model was subsequently integrated into a riser reactor model for pilot level simulations, via the extrapolation of the results obtained based on the transient model for the fixed-bed reactor to the steady-state behavior of a riser reactor. In particular, a unique deactivation factor Phi, reflecting catalyst condition, was introduced in the model for the latter reactor to adequately account for the deactivation functions determined making use of the data acquired in the former. Simulation results demonstrate the significance of the first meters of the riser, as well as the effect of operation parameters, i.e, Phi, EP addition in the feed, inlet catalyst-to-oil ratio, on conversion and selectivities

A Model of Using the Asymmetric Polydopamine Thin Film for Mimicking Epithelial Folding In Vitro

The basement membrane (BM) is a biointeractive ultrathin network with distinct composition and organization of its epithelial and stromal sides, which render BMs with asymmetric biofunctions and mechanical properties. There are difficulties in the recapitulation of the highly hierarchical structure and function of BM. Here, the interfacial assembly method for the generation of BM mimics is applied. Dopamine is the starting material for the polymerization and assembly of polydopamine (PDA) into asymmetric materials. Compared to the PDA coating formed at the solid/liquid interface (≈20 nm), the PDA film formed at the air/liquid interface displays a thickness of ≈100 nm. Moreover, it possesses an asymmetric surface topography and an apparent Young's modulus of ≈1.0 MPa, which is structurally and mechanically similar to natural BMs. Of interest, the airside and the waterside of the PDA film exhibit differences in their adhesion affinity to the human skin keratinocytes. With stronger active mechanical processes between living cells and the waterside of PDA film, epithelial folding could be mimicked. Together, the PDA film is able to recapitulate the structural and mechanical complexity of natural BMs, indicating the prospective future of using PDA films for in vitro modeling cell-BM interaction and tissue formation

Disruption of Smad7 Promotes ANG II-Mediated Renal Inflammation and Fibrosis via Sp1-TGF-β/Smad3-NF.κB-Dependent Mechanisms in Mice

Smad7 is an inhibitory Smad and plays a protective role in obstructive and diabetic kidney disease. However, the role and mechanisms of Smad7 in hypertensive nephropathy remains unexplored. Thus, the aim of this study was to investigate the role and regulatory mechanisms of Smad7 in ANG II-induced hypertensive nephropathy. Smad7 gene knockout (KO) and wild-type (WT) mice received a subcutaneous infusion of ANG II or control saline for 4 weeks via osmotic mini-pumps. ANG II infusion produced equivalent hypertension in Smad7 KO and WT mice; however, Smad7 KO mice exhibited more severe renal functional injury as shown by increased proteinuria and reduced renal function (both p<0.05) when compared with Smad7 WT mice. Enhanced renal injury in Smad7 KO mice was associated with more progressive renal fibrosis with elevated TGF-β/Smad3 signalling. Smad7 KO mice also showed more profound renal inflammation including increased macrophage infiltration, enhanced IL-1β and TNF-α expression, and a marked activation of NF-κB signaling (all p<0.01). Further studies revealed that enhanced ANG II-mediated renal inflammation and fibrosis in Smad7 KO mice were also associated with up-regulation of Sp1 but downregulation of miR-29b expression. Taken together, the present study revealed that enhanced Sp1-TGF-β1/Smad3-NF-κB signaling and loss of miR-29 may be mechanisms by which deletion of Smad7 promotes ANG II-mediated renal fibrosis and inflammation. Thus, Smad7 may play a protective role in ANG II-induced hypertensive kidney disease. © 2013 Liu et al.published_or_final_versio